The present invention relates to a silver halide color photographic light-sensitive material, and more particularly to a silver halide color photographic light-sensitive material which comprises a cyan image forming layer capable of forming a cyan image having an excellent absorption spectrum, and which has a very excellent adaptability to processing.
Color images are usually obtained with the formation of dyes effected by the coupling reaction between the oxidized product of a color developing agent and couplers. In a multicolor photographic element, the subtractive color process is usually used to form a color image; the dye produced by the coupling is normally a cyan, magenta or yellow dye formed in or adjacently to a silver halide emulsion layer having its sensitivity to the wavelength region of the light that is to be absorbed by the image dye; i.e., a silver halide emulsion layer having its sensitivity to the red, green or blue region of the spectrum.
The characteristics which a coupler is required to have include, e.g., such a good color reproducibility that the color of the dye formed from it has a sharp-cut capability, and a good resistance to light, and the like.
As cyan couplers that meet such characteristics requirements, there have often been used phenol-type compounds or naphthol-type compounds. Particularly, naphthol-type compounds, since the dye formed therefrom has its absorption maximum (.lambda.max) in a longer wavelength region and has little subabsorption in the green region, have been practically used in producing high-speed color negative light-sensitive materials.
However, most dyes formed from those couplers, whether of the naphthol type or of the phenol type, have a large shortcoming that they, when in contact with ferrous ions, become discolored. Namely, in an ordinary development method, there is produced a large amount of reduced ferrous ions in the bleaching or bleach-fixing process, which ions reduce and discolor the cyan dye that has been formed by color development, thus causing the development to become unstable.
Particularly, in recent years, there is a tendency that the developer's replenishing rate is reduced or the silver content of color light-sensitive materials is increased for the purpose of improving the sensitivity, image quality, etc. This is a tendency toward the increase in the ferrous ion concentration in the bleaching process, thus bringing about severer reduction-discoloration conditions against the cyan dye. In view of this, it is natural that there arises a need for the development of cyan couplers that will hardly be discolored.
As the coupler that causes no reduction discoloration of the cyan dye formed therefrom in the bleaching or bleach-fixing process, there are known those couplers in which the 2nd and 5th positions of phenol are substituted with an acylamino group, as described in U.S. Pat. No. 2,895,826, and Japanese Patent Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O.P.I. Publication) Nos. 112038/1975, 109630/1978, 163537/1980, and the like. Any of these couplers has its absorption maximum in the shorter wavelength portion of the red region of the absorption spectrum of the formed dye, and also has much absorption in the green region, and thus it is undesirable for the color reproduction.
In addition, those phenol-type couplers having ureido group in the 2nd position of phenol are described in British Pat. No. 1,011,940, and U.S. Pat. Nos. 3,446,622, 3,996,253, 3,758,308 and 3,880,661. Any of these couplers, like the above-mentioned couplers, also has its absorption in the shorter wavelength portion of the red region of the absorption spectrum of the formed dye, the absorption being undesirably broad for the color reproduction, and some of these couplers form their dye that is discolored during the bleaching process; this is the drawback of these couplers.
On the other hand, as the coupler improved on the discoloration of the cyan dye formed therefrom, the absorption spectrum of which cyan dye has its absorption maximum in a relatively longer wavelength portion, there are known those couplers as described in Japanese Patent O.P.I. Publication No. 65134/1981, which are such that the 2nd position of phenol is substituted with a particular ureido group, but they are still not considered sufficient with respect to their absorption maximum wavelength.
Further, those ureido group-substituted phenol-type couplers as described in Japanese Patent Application Nos. 90334 to 90336/1981 and 131312 to 131314/1981 are ones capable of forming cyan dyes that are not discolored during the bleaching process, and the absorption spectrum of the resulting dye has its absorption maximum in a longer wavelength portion.
It has been found, however, that in the cyan dye formed from these ureido-substituted phenol-type couplers, in a higher color density area, the absorption maximum (.lambda.max) in its absorption spectrum is in a considerably long wavelength portion of the red region, but, in a lower color density area, the .lambda.max shifts toward the shorter wavelength side. Namely, it has become apparent that the .lambda.max varies according to the density of a color image as illustrated in FIG. 1.
Thus, due to the change in the .lambda.max, the color in a lower density area becomes more bluish than that in a higher density area. It goes without saying that it is an undesirable phenomenon, hindering the true reproduction of color. Accordingly, this is the reason that there is desired a color light-sensitive material the dye formed from which has no change in the .lambda.max and has a sufficient absorption wavelength portion in its lower density area, and is not discolored.
It is therefore a first object of the present invention to provide a silver halide color photographic light-sensitive material capable of forming a cyan color image whose hue is little affected according to the change in the color density thereof.
It is a second object of the present invention to provide a silver halide color photographic light-sensitive material with the formed dye image thereon having in either a higher density area or a lower density area its .lambda.max in a sufficiently long wavelength portion of the red region and having little absorption in the green region.
It is a third object of the present invention to provide a silver halide color photographic light-sensitive material whose developed dye image is little or not discolored by ferrous ions during the bleaching process.